0000000000074545

AUTHOR

Eleftherios Archavlis

Spinal Intradural Intramedullary Dissemination in the Absence of Intracranial Relapse of a Previously Radically Treated Temporal Lobe Glioblastoma Multiforme

Intracranial glioblastoma multiforme (GBM) constitutes the most frequent and unfortunately aggressive primary central nervous system malignancy. Despite the high tendency of these tumors to show local relapse within the brain after primary therapy, dissemination into the spinal axis is an infrequent event. If spinal metastases occur they are leptomeningeal in the vast majority of cases and always in the context of intracranial progressive disease. Spinal intramedullary metastases of intracranial GBM have rarely been described to date. We report the unique case of a young woman with subacute progressive paraparesis due to spinal intramedullary metastases of a temporal lobe GBM despite the re…

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Comprehensive Anatomic Assessment of Ipsilateral Pterional Versus Contralateral Subfrontal Approaches to the Internal Carotid Ophthalmic Segment: A Cadaveric Study and Three-Dimensional Simulation

Objective Medially pointing aneurysms of the ophthalmic segment of the internal carotid artery (oICA) represent a neurosurgical challenge. Conventional ipsilateral approaches require internal carotid artery and optic nerve (ON) mobilization as well as anterior clinoidectomy (AC), all associated with increased surgical risk. Contralateral approaches could provide a better exposure of the superomedial aspect of the oICA, ophthalmic artery, and superior hypophyseal artery, sparing AC and internal carotid artery or ON mobilization. However, the microsurgical anatomy of this approach has not been systematically studied. In the present work, we exhaustibly analyzed the anatomic and morphometric c…

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Rates of Upper Facet Joint Violation in Minimally Invasive Percutaneous and Open Instrumentation: A Comparative Cohort Study of Different Insertion Techniques.

Background Minimally invasive pedicle screw placement may have a higher incidence of violation of the superior cephalad unfused facet joint. Study Aims We investigated the incidence and risk factors of upper facet joint violation in percutaneous robot-assisted instrumentation versus percutaneous fluoroscopy-guided and open transpedicular instrumentation. Methods A retrospective study including all consecutive patients who underwent lumbar instrumentation, fusion, and decompression for spondylolisthetic stenosis and degenerative disk disease was conducted between January 2012 and January 2016. All operations were performed by the same surgeon; the patients were divided into three groups acc…

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A novel minimally invasive, dorsolateral, tubular partial odontoidectomy and autologous bone augmentation to treat dens pseudarthrosis: cadaveric, 3D virtual simulation study and technical report.

OBJECTIVE The goal of this study was to demonstrate the clinical and technical nuances of a minimally invasive, dorsolateral, tubular approach for partial odontoidectomy, autologous bone augmentation, and temporary C1–2 fixation to treat dens pseudarthrosis. METHODS A cadaveric feasibility study, a 3D virtual reality reconstruction study, and the subsequent application of this approach in 2 clinical cases are reported. Eight procedures were completed in 4 human cadavers. A minimally invasive, dorsolateral, tubular approach for odontoidectomy was performed with the aid of a tubular retraction system, using a posterolateral incision and an oblique approach angle. Fluoroscopy and postprocedur…

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Maintenance of Integrity of Upper Facet Joints during Simulated Percutaneous Pedicle Screw Insertion Using 2D versus 3D Planning

Background No studies have directly and quantitatively compared two-dimensional (2D) and three-dimensional (3D) planning as applied during conventional percutaneous or navigated percutaneous pedicle screw placement. Study Aims This lumbar pedicle-based stabilization simulation study aimed to investigate the risk of upper facet joint violation (FJV) during posterior percutaneous pedicle screw placement with conventional 2D planning of screw implantation (as a model for fluoroscopically guided screws) compared with 3D planning (as used with navigation techniques). Methods The placement of monosegmental lumbar pedicle screws using the data sets of 250 consecutive patients was simulated. Conve…

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Cervical Motion Preserving Procedures (TDR)

Symptomatic cervical degenerative disc disease leading to radiculopathy is a common problem with an incidence of 0.83–1.79 per 1.000 person years. While many episodes of radicular symptoms can be successfully managed by conservative therapy, patients with refractory symptoms or a significant paresis are candidates for a surgical treatment. However, different surgical techniques are available to treat cervical degenerative disc disease, as anterior cervical discectomy without fusion, anterior cervical discectomy with fusion or posterior foraminotomy. Anterior cervical discectomy with fusion as described in the 1960’s (Chap. 3) is currently regarded as the gold standard. Although ACDF provide…

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Tentorial Incision vs. Retraction of the Tentorial Edge during the Subtemporal Approach: Anatomical Comparison in Cadaveric Dissections and Retrospective Clinical Case Series.

Abstract Objective The aim of this study was to compare tentorial incision (group A) versus retraction and tack up suture (group B) of the tentorial edge during the subtemporal approach for surgery in the high basilar region. Design 24 cadaveric dissections and 4 clinical cases of aneurysms of the high basilar region are presented. Assessment included visibility and operability afforded by either tentorial incision creating a dural flap (group A) or retraction of the tentorial edge and tethering with a suture (group B). Four patients, two with superior cerebellar artery aneurysms and two with proximal posterior cerebral artery aneurysms were treated with each approach. Results In the quanti…

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